drm/radeon/kms/avivo: fix some bugs in the display bandwidth setup

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>

drivers/gpu/drm/radeon/radeon_fixed.h

@@ -38,6 +38,23 @@ typedef union rfixed {
 #define fixed_init_half(A) { .full = rfixed_const_half((A)) }
 #define rfixed_trunc(A) ((A).full >> 12)
 
+static inline u32 rfixed_floor(fixed20_12 A)
+{
+	u32 non_frac = rfixed_trunc(A);
+
+	return rfixed_const(non_frac);
+}
+
+static inline u32 rfixed_ceil(fixed20_12 A)
+{
+	u32 non_frac = rfixed_trunc(A);
+
+	if (A.full > rfixed_const(non_frac))
+		return rfixed_const(non_frac + 1);
+	else
+		return rfixed_const(non_frac);
+}
+
 static inline u32 rfixed_div(fixed20_12 A, fixed20_12 B)
 {
 	u64 tmp = ((u64)A.full << 13);

drivers/gpu/drm/radeon/rs690.c

@@ -260,8 +260,9 @@ void rs690_crtc_bandwidth_compute(struct radeon_device *rdev,
 
 	b.full = rfixed_const(mode->crtc_hdisplay);
 	c.full = rfixed_const(256);
-	a.full = rfixed_mul(wm->num_line_pair, b);
-	request_fifo_depth.full = rfixed_div(a, c);
+	a.full = rfixed_div(b, c);
+	request_fifo_depth.full = rfixed_mul(a, wm->num_line_pair);
+	request_fifo_depth.full = rfixed_ceil(request_fifo_depth);
 	if (a.full < rfixed_const(4)) {
 		wm->lb_request_fifo_depth = 4;
 	} else {
@@ -390,6 +391,7 @@ void rs690_crtc_bandwidth_compute(struct radeon_device *rdev,
 	a.full = rfixed_const(16);
 	wm->priority_mark_max.full = rfixed_const(crtc->base.mode.crtc_hdisplay);
 	wm->priority_mark_max.full = rfixed_div(wm->priority_mark_max, a);
+	wm->priority_mark_max.full = rfixed_ceil(wm->priority_mark_max);
 
 	/* Determine estimated width */
 	estimated_width.full = tolerable_latency.full - wm->worst_case_latency.full;
@@ -399,6 +401,7 @@ void rs690_crtc_bandwidth_compute(struct radeon_device *rdev,
 	} else {
 		a.full = rfixed_const(16);
 		wm->priority_mark.full = rfixed_div(estimated_width, a);
+		wm->priority_mark.full = rfixed_ceil(wm->priority_mark);
 		wm->priority_mark.full = wm->priority_mark_max.full - wm->priority_mark.full;
 	}
 }

drivers/gpu/drm/radeon/rv515.c

@@ -889,8 +889,9 @@ void rv515_crtc_bandwidth_compute(struct radeon_device *rdev,
 
 	b.full = rfixed_const(mode->crtc_hdisplay);
 	c.full = rfixed_const(256);
-	a.full = rfixed_mul(wm->num_line_pair, b);
-	request_fifo_depth.full = rfixed_div(a, c);
+	a.full = rfixed_div(b, c);
+	request_fifo_depth.full = rfixed_mul(a, wm->num_line_pair);
+	request_fifo_depth.full = rfixed_ceil(request_fifo_depth);
 	if (a.full < rfixed_const(4)) {
 		wm->lb_request_fifo_depth = 4;
 	} else {
@@ -992,15 +993,17 @@ void rv515_crtc_bandwidth_compute(struct radeon_device *rdev,
 	a.full = rfixed_const(16);
 	wm->priority_mark_max.full = rfixed_const(crtc->base.mode.crtc_hdisplay);
 	wm->priority_mark_max.full = rfixed_div(wm->priority_mark_max, a);
+	wm->priority_mark_max.full = rfixed_ceil(wm->priority_mark_max);
 
 	/* Determine estimated width */
 	estimated_width.full = tolerable_latency.full - wm->worst_case_latency.full;
 	estimated_width.full = rfixed_div(estimated_width, consumption_time);
 	if (rfixed_trunc(estimated_width) > crtc->base.mode.crtc_hdisplay) {
-		wm->priority_mark.full = rfixed_const(10);
+		wm->priority_mark.full = wm->priority_mark_max.full;
 	} else {
 		a.full = rfixed_const(16);
 		wm->priority_mark.full = rfixed_div(estimated_width, a);
+		wm->priority_mark.full = rfixed_ceil(wm->priority_mark);
 		wm->priority_mark.full = wm->priority_mark_max.full - wm->priority_mark.full;
 	}
 }